Thada Adel, Acquisitor is a rare Legendary Creature — Merfolk Rogue card from Worldwake (WWK), collector number 40. Current market price: $10.55 (foil $40.79), TCGplayer market prices via Scryfall.
Islandwalk (This creature can't be blocked as long as defending player controls an Island.) Whenever Thada Adel deals combat damage to a player, search that player's library for an artifact card and exile it. Then that player shuffles. Until end of turn, you may play that card.